A. Field of Invention
The invention is directed to the field of articles used to secure filament with respect to a mandrel during a filament winding process. More specifically, this invention is a universal pin ring mountable at both ends of a mandrel in the fiber turnaround region, the pin ring being useful to prevent fibers from slipping and thus having an incorrect orientation in the turnaround region. The invented universal pin ring is of such a configuration that it can be used in winding components in the range of sizes from very small to very large. The terms `pin ring` and `pin strip` are used interchangeably herein. The figures depict both a pin strip by itself and a pin ring installed in the preferred position on a mandrel.
B. The Background Art
In the prior art, only one manufactured pin ring was available. It was a molded tube about 2.5 inches in diameter that included a single row of triangular-shaped fin-like protrusions from its exterior diameter. These protrusions were used to anchor filament during the winding process. This pin ring was developed for winding down hole tubing used in the oil drilling industry. When other parts were to be wound, the manufacturer would typically have to make a pin ring by hand that was tailored to the specific application, since no universal pin ring was available.